Hellgate
Member
I was sighting in and shooting 5 shot groups on a sand bag rest @ 100yds. I noticed that beginning each group the first round went high & right of the other 4. Roughly .5-1.5" high and .5 tp 1 inch right. I repeated it several times Using the bolt release to chamber the first round. Once I saw the pattern I varied the chambering of the first round by trying full mags, only 5 in the mag, first round on the right, first round on the left, first round put in the chamber by hand and bolt eased over it, first round chambered by hitting the bolt release. The only thing I forgot to do was to pull the charging handle all the way back and let it slam home. This is with the Sierra 65gr Game King over 24grs W748 OAL 2.25", Fed 205 primer in weighed Federal mil spec brass. When I shot some 52 & 53gr match bullets I did not notice much of a difference in first round POI. The reason this is bothering me is I want an AR calling gun that throws the first round into the same group. The first shot is usually the one that counts but I've hit several on the 2nd, 3rd and in one case the 12th shot. What do I need to do to fix this? The upper was recently rebarreled with a CobraTac 16" nitrided SS match HBAR 1:8. Without the flier I'm getting 0.6-0.8" groups with the 65gr GK and in the .3s & .4s with the 52gr match bullet. The barrel was warm.
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